[CAG CheechDogg]

Make a new template call it

block_html_nonmembers

In that template add the following

<vb:if condition="is_member_of($bbuserinfo, 1)">
<li>
	<div class="block smaller" id="members_not_logged_in">
		<div class="blocksubhead">
			<a class="collapse" id="collapse_block_html_{vb:raw blockinfo.blockid}" href="{vb:raw relpath}#top"><img alt="" src="{vb:stylevar imgdir_button}/collapse_40b.png" width="16" height="16" id="collapseimg_html_{vb:raw blockinfo.blockid}"/></a>
			<span class="blocktitle">{vb:raw blockinfo.title}</span>
		</div>
		<div class="widget_content blockbody floatcontainer">
		<div id="block_html_{vb:raw blockinfo.blockid}" class="blockrow">
			{vb:raw content}
		</div>
		</div>
	</div>
	<div class="underblock"></div>
</li>
</vb:if>

Now you can add a block using the template "block_html_nonmembers" instead of "block_html" and it will only display to those who are logged in ...